I'd like to install an older version of firmware to replace current (01-02.24). So, I downloaded 1.01.11A at http://daniel.haxx.se/sansa/mi4.html, and received two files:
1. BL_SD_boardSupportSD.rom
2. PP5022.mi4
What should I do now? What do I do with these two files? I don't mind wiping out all my files because I want to get rid of some "bad" tracks hiding in a folder called "Unknown," which becomes invisible when connected to my G5. Also, I've read that the older firmware enables us to see the player on the desktop.
Any suggestions are much appreciated.
Thanks!

Thanks very much for your quick reply.
I'm trying to follow the link's directions. What is the root of this directory? All I see is: 1. .fseventsd
2. .Trashes
3. VERSION.TXT
Do I simply drag and drop the .mi4 firmware file right beside them?
Then, before ejecting the e250, I will format it as an MS-DOS (FAT12), Right?
Thanks again for your help.

Sorry. I should have mentioned I am a Mac user. So, when I select the Sansa e250, it shows me its contents—the 3 files I mentioned above—in the panel to the immediate right. Since none is a folder, it appears that my only option is to put the .mi4 firmware file right beside them, or in the same level of the directory.

While in Recovery mode I added the PP5022.mi4 file from an 01.01.11A download to the device. Then I disconnected it, turned off the lock and found it had recovered. That's a relief.
Since the recovery, I found and downloaded a folder called "Bricked," that contains:
1.) BL_SD_BOARDSUPPORTSD.ROM
2.) PP5022.MI4
3.) Sansa.fmt
Should I do something with any of them?
Because I still have all the problems that made me want to delete all files I had ever added, including that:
1.) Although duplicates of several tracks and three complete albums/audiobooks are seen when deciding what to play, they are NOT seen when mounted on the desktop;
2.) I never know whether the e250v1 will show up on the desktop. So, I change the USB Setting back and forth between MSC and MTP, and set visible files on my desktop to be visible. And, finally, I want to
3.) Install Rockbox and/or other add-ons without fear of bricking the device.
Or, perhaps this is too much to expect, given that I may simply be another Mac whiner trying to crash a Windows party.
Any Mac-friendly suggestions are much appreciated.
Thanks!